Conventionally, as a photodetector, there is known a so-called bolometer-type infrared detector for detecting infrared rays by using a material, the resistance value of which varies depending on temperature. As the bolometer-type infrared detector, for example, Patent Document 1 has disclosed that which is provided with a bolometer element for detecting infrared rays made incident and a reference element for detecting temperature variation caused by variation in use environment, in which signals output by these elements are used to calculate signals excluding the influence of temperature variation caused by variation in use environment, thereby detecting infrared rays. The infrared detector described in Patent Document 1 is provided with a bolometer element having a bolometer thin film supported via a cavity on a silicon substrate which is a diurnal capacity body and a reference element having a bolometer thin film formed via a sacrifice layer on the silicon substrate.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 10-227689*2(JP10227689A)